In the offshore segment of the petroleum industry one of the prevalent problems has been the connection of an offshore platform to the pipeline which normally carries petroleum products to an onshore storage area. Usually one or more wells at the bottom of the ocean are connected to a common line which carries the products to a riser or conduit supported by the platform. The riser directs the crude liquid or gas product upwardly to a separation system at the platform's deck prior to the product being conducted away by another such pipeline, or shipped away by tanker.
As a matter of practice, the connection between the pipeline and the riser at the platform, is made by welding the pipe joint to the riser through the use of divers and/or highly technical equipment which is lowered to the sea floor. In the instance of relatively deep waters the normal problem of making the above noted connection is substantially compounded by the hyperbaric atmosphere which limits the use of personnel.
Toward simplifying this laying of the desired pipeline the present invention provides a means whereby the lower end of the fluid carrying riser is pivotally connected at the platform to an extension member. In the resting position the extension member is disposed substantially uprightly so that its open end is at the water's surface. The pipeline segments can then be welded to the extension above water.
As additional segments are added to the pipeline, the extension is lowered to a normal resting position at the ocean floor. After sufficient settling time, the connection to the platform supported riser is solidified in place by the introduction of grout, cement, or other material which can be conducted to the ocean floor through piping, tubing, or the like and caused to solidify when in place.
It is therefore an object of the invention to provide means for connecting a platform supported riser conduit to a pipeline without the necessity of operating underwater or utilizing divers. A further object is to provide an offshore platform including means for connecting a riser member to the pipeline through the use of a pivotally connected riser extension. A still further object is to provide an offshore platform of the type contemplated which simplifies the laying of a pipeline from the water's surface to the floor, after being initially connected to the riser lower end through a pivotally connected joint.